Inductor switch



Aug. 3, 1943. H. w. WILLIAMS ET AL INDUCTOR SWITCH Filed July 26, 1940 3 Sheets-Shea?l l \\\\\\\\M /z lli@ l a '.6 /r

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INVENTORS Aug- 3, 1943 H. w. WILLIAMS ET Al. 2,326,086

INDUCTOR SWITCH Filed July 26, 1940 3 Sheets-Sheet 2 J S m z 3 M 1| IT w z 5 Q, w M 4 L 1 7 d arm m 7 Q O l 4 f :1 1 3 Y z r l r1 rJ m S .M/ -T L ,.J uw 11m w M m ilu m n Q w n -i @g INN -l @E m H a 4 4 M 2 m w 4 4 o W O J d ffl l S L- Q 2 I S T l.. 4 w Z Aug? 3, 1943- H. w. WILLIAMS ET AL INDUCTOR SWITCH Filed July 2e, 1940 5 Sheets-Sheet. 3

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INVENTORS Haro/did! M//Y//a/ms, Paa//Y/Var/H A? ozya/d wlTNEssEs: l v@ WM ATT NEY` Patented Ang. 3, 1943 INDUCTOR SWITCH Harold W. Williams, Nut-ley, Paul M. Martin,

Jersey City, and Donald H. Baum, Ridgewood,

N. J., assignors to Westinghouse Electric, Elevator Company, tion of Illinois Jersey City, N. J., a corpora- Application July 26, 1940, Serial No. 347,650

3 Claims.

Our invention relates to inductor switches and, more particularly, to inductor switches of the character utilized for controlling the acceleration and stopping of elevator cars in elevator systems in which the switches and their coils are mounted on the cars in position to be operated by inductor plates mounted on the hatchway Walls.

One object ofthe invention is to provide an inductor switch which will operate accurately regardless of variations in the exciting current in the switch coil `due to coil heating or voltage variations due to the ageing of `parts of the system, variable loads on parts of the system or v-ariation in the supply line voltage..

Another object is to provide an inductor switch for` elevator cars in whichv the contact members will operate in exactly the same vertical position relative to the inductor plateV regardless of variation in the horizontal distance or air gap betweenr the plate and the wear of guide shoes, or other reasons.

A further object is to provide 'an' inductor switch which will use less current than heretofore necessary.

A furtherobject is to provide a narrow, deep and tall form of inductor switch to permit the mounting of a together without interfering with each other.

A still further object of our invention is to provide an inductor switch in which the contact members will operate quickly and snappily to prevent excessive contact wear and secure accurate results from the operation of the switch.

It is also an object to provide an inductor switch which may be easily and economically constructed, installed, operated, and maintained in operation.

For a better understanding of the invention, reference may be had to the accompanying drawings, in which:

Figure 1 is a top plan view of an inductor switch embodying our invention mounted on the top of a car in a hatchway;

Fig. 2 is a view in side elevation ofthe nductor switch illustrated in Fig. 1, with the switch and inductor plate in unoperated position with relation to each other;

Fig. 3 is a view in side elevation of the inductor switch illustrated in Fig. 1 with the inductor plate and switch in their operative position;

Fig. 4 is an enlarged view, in front elevation, of the inductor switch and coil shown and illustrated in Fig. 1;

Fig. 5 is a top plan view of the switch mechanism illustrated in Fig. 4;

switch due to car sway,

plurality of such switches close (CI. 17d-336) Fig. 6 is a view in illustrated in Fig. 4;

Fig. 7 is a top plan view of the upper pole plate for the switch illustrated in Fig. 5;

Fig. 8 is a view in side elevation of the upper pole plate illustrated in Fig. 7;

Fig. 9 is a view in front elevation of the upper pole plate of Fig. 8

Fig. 10 is a top plan view of the operating clip mounted on the armature in Fig. 5;

Fig. 171 is a view in side elevation of the operating clip of Fig. 10;

Fig. 12 is a view in end elevation of the operating clip of Fig. 10

Fig. 13 is a view in side elevation of the stop clip mounted on the armature in Fig. 5;

Fig. 14 is a view in end elevation of tho clip of Fig. 13,'

Fig. 15 is a top plan view of the cover bracket illustrated in Figs. 5 and 6; and

Fig. 16 is a view in side elevation of the cover bracket of Fig. 15.

Referring more particularly'to the drawings, we have illustrated an electromagnetic device such as an inductor switch I as mounted on top of a car C in position to be operated by an inductor plate 2 mounted in any suitable manner on the wall 3 of the hatchway in which the car operates. Only a small portion of the car and the hatchway are shown.

'I'he inductor switch comprises a frame 4 of non-magnetizable material, a top plate 5 and a bottom pole plate 6 of magnetizable material mounted on the frame, a core 1- of magnetizable material mounted between the outer ends of the plates, a coil 8 mounted on vthe core, a pair of switches S and l0 disposed on the top pole plate, and a. cover Il and cover bracket Ha for the Switches. f

The frame 4 comprises a hollow rectangular box-like casting provided with plurality oi screw-threaded holes by means of which it may be secured with machine bolts i3 to an angle bracket I4 fastened to the top of. the elevator car C by machine bolts i5.

The magnetizable core 'l is of rectangular shape in cross section and is much wider than it is thick. Hence the coil 8 mounted on the core has an oval shape in cross section as shown in Fig. 5, rather than the usual cylindricall form. This permits-the use of a narrow form of inductor switch so that a plurality of l them may be mounted side by side without Ltaking up a large amount of space. The lower end of the core is side elevation of the switch stop ' plate E by a pair 0i f press displacing a portion ofl the'plate.

. opening a (Fig. l5)

' Il which may be fastened .6) 'so that the frame;

- The coil 8 is provided with-lea extend through an insulating. ring 25 in Y which hold itfgon the frame and f 'porting the switches. The armature.Supporting` s the cent secured in a depression vl? in the bottom pole machine screws i8. The depression may be made by the operation of a punch The uppasses through a punched out in the cover bracket lla underside Vof the top pole per end of the coreV and rests against the plate 5 to which itis' secured by a pair of mae chine screws I9.

The cover bracket sidel of the toppolev plate tubular rivets 20. .Y The outer ends 2l the cover .bracket are turned inwardly to provide l la is fastened to the under- Vand V22 of supports tor the cover screws 23. Y y Y The rear ends of the top pole plate 5 and the bottom pole plate 6 are securely 'x'ed to the top' and bottom of the mounting frame by a plurality of machine screws 24 and 24a (Figs. 5 and the top plate', the cover bracket.the core, the coil,v and the bottom plate forinarm structural unit.A n;

wires 25 which the, Side of the mounting frame in which theymay be connected to 'aV terminal panel (not shownl in the usual manner.

vThe toppole plate ors'witchriraulneiligs 31 and 9) is pressedout of heavy magnetisable plate material in somewhat the form 'of a :Short handled paddle. holes 21 through which to hold the plate and the cover gether. The plate is also provided' the rivets 2 9 may entend bracket, rmlsf towitlr avpluralitypof Yholes i118 for thefmachinescrews 4 El plmflty' 0f holes lSa for the machine screws i9 passing into thcor'el; f ,i 'ji l' When' the top plate 'is shaped;V it lisprovided iwith a pair ofswitch-Supportinglg39 `and 3l, a pair'of lockout lugs 32 and 33; anda .pair of annature-supportinglugs34 and 35. f` The switch-supporting lugs 3Q arid-Si are 'disend 29 of the toprplate andare beitlupwiidlyat right arigisjtoitue. faeeof tue piste. l., unable screw-'threaded' holes e1 disposed` inthe switch Tls tolec'eiv Viiiichiiie screws forsup i l gs .g'ahd 35 are ieeeteu fue central portion of the plat-e yapc y y angles tothe plate. 'l-hlug Seis provided with aiorwardly extendor stationerylauxmefnbef einer; u

' s provided withr l'jsiihilar forwardlya:

member( 351i igor tending ori stati-of ery forming pains Afor maglie-tie nur liiowi'ne tothel armatures to te hereieffieroescubea. Theiocr; out lugs t2 andY 33am disposed on thein'ii'er ends of the plate 5 and are bent .upwarmt athghtangies to the fece of the' 'plete biitat a slightanglewith referenceto the edges o'thje plate. The use of the lugsV 32 and 33 will be desenbeaiater. l

The central portion ofthepaddle end of the thereto by a pair .of

by means of va pair of bent upwardly and then y It is provided with 'a paire;

v spot-welded'to the innerside'o plate tis out away et se'topovicie two narrow Y ami' at rn the eine: im@

setns, r A

and esi provide restricted narrow sections S1 ai eoiftiqtfthe eine to the outer right han@ `eine werent. The restricted Section-s A:si

' 'and 3s extend into and au fof support;

ifi-gene retreat rugs storie 53. frhe'smie se and ao are traces ey the cio-ss' pretese.

in@ magneet aux which new from 'tact members are tact membersare forced into engagement by the 1c'ontactarm .3.

Two spacing lingers are used to secure a stiibut flexible limiting element. the lpresent to remain normally closed eX- cep't when opened by thegoperation of the switch mechaiisin .'V Therefore the switch arm 43 is bent slightly tobias,- its contact member into contact the face of the contact member 42 on the switch arm lle.

Tne base ends 13a and filial. of the switch arms extend rearwardly from the insulating sheets and are connected to "a pair of suitable conductors 5i? and El for the cir'cuitto be controlled by switch; The conductors-1 passY from the switch arrnjends through an insulating ring :o2Y into the interior oithe. frame l where they may befconnected to a `panelboard (notv shown) An insu lating plug 53 is riveted to the innerside ci' the outer' endof the springarrn Q3 to aiorda means by which the con act members el l2l may be opened. Y 15' An armature l is provided ioractuatinethe insulating plug 53 te openthe `contact members el and e2. The armature isan elongatedjpiecc of rectangular magnetiaable material having'its leitihandlend Apyotally a'ttacherl tothe armature supporting lug mounted insnch position thatitextends between the arm 35u-and theplate -bodywith its Vtree outer end disposed d t i free end of the armature shouldnetfd vto the end oi the lockout lug but should dto i portionV of theV locliroutlug,ap.n proximately as indicated in Fig. G. conabout the central 'struction showy-,illes been found. tcgive the best performance practice. stop clip 5'? of biassmor magnetivzable material ,(lifiga, 52

the'free endiof the armature 5; such position that its free end will strikeragainst Vthe inner' face Voigtlie lockout v lug when thesarm'ature is inits operated position' soies tovlimit theV outward movement of the armature. Howeverg for some operations; it may Vbe more desirable to use an ironsto" cli "instead or brass in order to secure better Voperation when self" -holding is required.

An operating clip 5,3 of ,brassor other suitable non-magnetizablc material is also spot-ewelded to the outer end portion of the armature oil-so that its free end will engagethe insulating plug on the arm i3- t'o'cause' that arm tolroctfe Vto open position when the armature g isactuateil' The clip 53 is provided with `a central aperture 53 through which theV free end vof the brass stop clip El extends into'its stop position witl'irelation to'thelcckout lug.

In Fig; V5, the position of the various parts'oi the switch Eilrare 'shown in their normal position when the switch is not being subjected `to the in i'luence of an inductorplateiand .switch 'o is shown in its operated position 'under the influence and 44 supported in a plurality of insulatinstance it is assumed that the con-L by a thin hingespring; 55; and

whenit is in operative andthe relay coil 8 is of the inductor .plate 2 position relative` thereto energized.

n Should be noted that the spring strength ofV the switch arm `Maand the position of the outer end of the operating clip 58 should be such that the contact members will be closed and the base of the clip and the armature end will be almost, but not quite, in engagement with the lockout lug 32 when' the inductor plate is not near the switch. The partsmay be easily adjusted to the correct unoperated position by bending either the switch arm 43 or the clip 58, or both, slightly after the parts are assembled.

Figs. 4 to 16 are practically full-size drawings of the inductor switch. The inductor plate used in practice for this size inductor switch is approximately Zei thick, 3 to 4" wide, and 'I1/4 long or longer. The plate should be so mounted in a vertical position on the hatch wall that it will overlap `the inductor switch in a horizontal direction a distance of approximately 11/8, substantially as shown in reduced size in Fig. l. The plate is so mounted to cause its free side to come near the free end of the armature as the inductor switch passes the plate, for the purpose of securing the most Ydesirable operation of the armature.

An assumed operation of the device follows:

It will be assumed that the car C on which the inductor switch l is mounted is disposed in the upper part of its hatchway, that it is moving downwardly in the hatchway and that the coil 8 of the inductor switch has been yenergized to cause the switch 9 to be opened as the inductor switch comes opposite the inductor plate 2 mounted on the wall of the hatchway.

The energization of the 'coil 8 energizes the core 1 which causes magnetic flux to pass through the air from one end of the core to the other. The flux paths are very complex and applicants will not attempt to describe them. However, with applicants structure, the switch will operate as follows. Assume now that the car moves the switch on downwardly until it and the plate are in approximately the position shown in Fig. 2. At this point some of the leakage flux ows from the end of the upper pole plate through the air to the inductor plate, through a portion of the inductor plate and across the air gap between the inductor plate and the bottom pole plate to the lower end of the core. As the switch moves on down along the plate, the ilow Y of ilux increases through the plate. 'Ihis leakage flux starts from the upper end of the core, passes into the center portion of the top plate, thence along the plate where some of it passes into the armature as indicated by the arrow 62. Some part of it flows through the armature supporting lug 35and along the arm 35a to a point where it crosses the air gap (see arrow 63)` between the armature and the arm and then follows the armature. Another portion of the flux ilows through the restricted portion 38 of the top plate which causes saturation of the restricted section 38 and results in a considerable drop in magnetic potential between the main part of the top plate and the turned-up lockout lug 33 at the end of the plate. Since the armature has a large ratio of cross-sectional area to air-gap permanence, it is not saturated and has, consequently, a lower drop in magnetic potential from the plate to the end of the armature than` appears in the section 38, in spite of the air gap between kthe plate and the armature. 'I'here is, then, a difference of magnetic potential between the lockout plate and the end of the armature, so that sufcient iiux iiows from the end of the armature through the small gap to the lockout to produce an appreciable attractive force between the two. This force aids the spring switch arm in holding back against any opening tendency of the armature.

It will be assumed now that the downward movement of the switch has progressed to a point where the upper edge of the inductor plate 2 is horizontally opposite the armature 54 as shown in Fig. 3 and that a greater portion of the flux starts to ow directly from the armature to the plate. This causes the armature 54 to start to move outwardly and it quickly reaches its full open position, as shown in Fig. 5.

When the armature starts to move outwardly, the iiux between the armature and the lockout and, consequently, the lockout force, decreases almost immediately to zero, so that, as soon as the armature starts to move, the total force resisting the movement decreases quickly, causing the armature to open the contact members quickly.

This, then, is believed to be the method of causing the snappy contact action set down originally as one of the desirable design features to be sought; for the excess of operating force over restraining force which is built up as soon as motion starts causes the armature to accelerate rapidly and open the contact members quickly. The armature movement without the lockout, with the switch moving slowly past the plate, would be slow and would stop if movement of the switch should stop.

Applicants believe that t t`-eory as to the ilow of in their f inductor switch is correct, but regardless of pcs iL-le error in the theory, applicants have round in practice that their forni of inductor switch uses much less current, that it opera es the armature more snappily, and that the switch operates with more accuracy regardless oi the horizontal spread between the plate and the armature and regardless of variations in voltage, coil heating, etc., than the ind tor switches with which they are acquainted.

Although we have illustrated only one form of our mirent... n, it is to oe understood that changes ein and modifications thereof may be made without departing from the spirit and scope of the invention.

We claim as our invention:

l. In an electromagnetic device, a core, a magnetizing coil disposed on said core. a pole plate of magnetizalle material. associated with the core, said pole plate havirN a central body portion and a restricted a extending from the body portion, an armature-supporting lug extending outwardiy from body portion, a lockout member disposed on restricted arm; a flux-conducting arm disposed on the armature-supporting lug and extending substantially parallel to the body ci the plate and in the direction of the lockout member, an armature disposed between the ilux conducting arm and the plate body, and a spring hinge pivotally mounting the armature on the armature-supporting lug with its iree end disposed adjacent to the lockout member in position to be actuated by an inductor plate when the coil is energized.

2. In an electromagnetic device, a core, a magnetizing coil disposed on said core, a pole plate of magnetizable material associated with the and described ed by Spring h ige between two portions of the opflate t6 pio 'a' plurality di patrf n the irme immun f tlie alhft'e, tle Vt'ite lo n of 'said d'spds aong the' am vextend- 'ol'al lockout lug of magnet Oife side of the oute lug batting' a length of the. amatuf'e', ed enditio of the' of magnetic poten-y of magnetablemat'erl associated .Wthftle centail bodylp'or# tion and a, restricted arm extending from thel body portion, meaifn{etZfCLbIeA lug disposed on one side ofthe 'outer end poton of the estcted f core, Said pole pltze lflavg al arzi, an' armati-"1re suiiportngug extending outwardly from the body portion t approximately ri nt Y'arfgles to the restricted' -rm, a fluxeoona ating afm disposed on Vthe 111g' and extending' su'lostanta'lly p'rallel to' the plate in the direction of the re'strtectlrm,sand aml armatue having Conducting rm ld; the' plate and hngedly mounted on the supporting lug and its other emiVV extending a'cjcntto' themagnetiza'lole lug on 

